Doubt I'll get a diagnosis here, but here are my symptoms. *admin edit* none of my doctors have ever been able to figure it out and I'm pretty much hopeless at this point...

Symptoms:
Severe apathy/abulia (I basically feel like I'm dead. Doing anything is no different from staring at a wall. I sit in my room all day and do almost nothing. This is different from depression because it's not associated with feelings of sadness, I literally feel nothing. The only thing I do during the day is walk the dog and the rest of the time I spend staring at the computer screen doing almost nothing. These symptoms get worse all of a sudden about an hour after I eat dinner at night, and my head starts to feel hurt and feel really strange. This severe apathy is normally symptomatic of damage to the frontal lobes of the brain but that's not the case in this case as both my MRI and CT scans were clean.

Sometimes I'll randomly start gagging, a lot of times after I got up from eating dinner, or after i started walking around.

constant weird sensations and pain on my scalp on the left side of my head

Periodic episodes of severe depression/anxiety where I have such a strong nervous feeling in my stomach that I barely eat anything.

I've done research and have been able to find nothing that fits my symptoms. I've already been tested for urea cycle disorders, Wilson's disease, and lyme disease and have had an MRI and a CT that showed nothing. My symptoms started ten years ago and I've been absolutely miserable ever since.